193Archivio Italiano di Urologia e Andrologia 2019; 91, 3 CASE REPORT Priapism induced by use of tamsulosin: A case report and review of the literature Marcelo Marconi 1, Pablo Pavez 2, Ignacio San Francisco 2, Paulette Narvaez 3 1 Andrology Unit, Department of Urology, Pontificia Universidad Católica de Chile, Santiago, Chile; 2 Department of Urology, Pontificia Universidad Católica de Chile, Santiago, Chile; 3 Department of Urology, Hospital Dipreca, Santiago, Chile. Numerous medications have been associated to the development of priapism as an adverse reaction, the most common are intracavernosal vaso- active agents, antipsychotics and antidepressants. Alpha block- ers, in particular tamsulosin which is widely used in different urological conditions, has been associated to priapism in only few case reports. We present the case of a healthy 45-year-old man who med- icated himself with two doses of 0.4 mg of tamsulosin due to a renal colic with spontaneous passage of a 3 mm stone. Eight hours after the second tamsulosin dose the patient developed a persistent painful erection not associated to sexual stimulation that lasted for 6 hours. He was admitted to the emergency room, and after history taking and physical evaluation the diagnosis of ischemic priapism was made. The patient denied consumption of any other medication or drug during the last month, blood tests in particular hemogram were normal and no recent history of pelvic trauma was reported. To achieve detumescence, five boluses of 200 mcg of phenylephrine were injected directly in the corpora cavernosa, no further proce- dures were needed. In the follow-up the patient had no new pri- apism episodes and he reported no problems with erections in sexual intercourse. Tamsulosin is one of most indicated medica- tions in urological general practice; though priapism has been rarely associated to its consumption the risk of this side effect exists, suggesting that patients should be counselled about it. KEY WORDS: Priapism; Tamsulosin; Adverse effect. Submitted 24 April 2019; Accepted 6 May 2019 Summary No conflict of interest declared. can also develop as a side effect of different medications and drugs, being the most common vasoactive intracav- ernosal injections, psychotropic medications and recre- ational drugs (i.e. alcohol, cocaine) (2). Alpha-blockers such as prazosin, terazosin and doxazosin have also been reported as an etiology of priapism. Tamsulosin, an alpha 1a blocker, has rarely been related to priapism; however, is one of the most indicated medications in general urological practice being the first therapeutic line for the management of benign prostatic hyperplasia (3) and treatment of distal ureteral stones (4). The objec- tive of this case report is to present a case of tamsulosin induced ischemic priapism. CASE PRESENTATION A healthy 45-year-old man with history of one renal colic episode with spontaneous stone elimination 12 months earlier, develops forty-eight hours before consultation a colic left flank pain and lower urinary tract symptoms, in particular urgency and increased urinary frequency, with no fever or macroscopic hematuria. The patient interpret- ed himself as developing a new renal colic episode so auto-medicated with ketorolac 10 mg three times a day and tamsulosin 0.4 mg once a day. The patient had no history of diabetes, hypertension, neurologic diseases, hematologic disease or any type of drug consumption or abuse. Thirty-six hours after the first symptoms and after two doses of tamsulosin the patient spontaneously elim- inated a 3 mm stone with no other incidents. The night before consultation approximately eight hours after stone elimination the patient woke up at 6 AM with his usual morning erection, he urinated with no difficulties but the erection persisted during the following 5 hours without any sexual stimulation at that time or the night before. The patient tried to achieve detumescence by walking and local ice application with no success at home. He was admitted at noon with already six hours of a constant, painful and unrelated to sexual stimuli erection. At admission, the patient was evaluated by the emer- gency room physician, who collected a completed med- ical history excluding consumption of drugs (cocaine, marijuana), antidepressants, antipsychotics, narcotics, intracavernosal injection of vaso-active agents, phospho- diesterase 5 inhibitors, or any other substance associated DOI: 10.4081/aiua.2019.3.193 INTRODUCTION Priapism is defined has a prolonged painful erection last- ing for more than 4 hours in the absence of sexual stim- ulation and remaining despite orgasm (1). The three main subtypes are ischemic, non-ischemic and stuttering, being ischemic priapism the most common form, charac- terized by absence of intracavernous arterial inflow. The incidence of priapism in the general population is low (0.5-0.9 cases per 100,000 person-years); however, it is considered a medical emergency and should be treated promptly to avoid further complications, in particular corporal fibrosis and erectile dysfunction. Although a specific etiology cannot be found in up to one-third of the cases of ischemic priapism, defined con- ditions such as blood dyscrasias and neurological disor- ders have been associated to its development. Priapism Marconi_Stesura Seveso 30/09/19 18:26 Pagina 193 Archivio Italiano di Urologia e Andrologia 2019; 91, 3 M. Marconi, P. Pavez, I. San Francisco, P. Narvaez 194 with priapism risk. The patient had no history of pelvic trauma either major or minor. The only drugs the patient had consumed in the last 48 hours were five 10 mg sep- arated doses of ketorolac and two 0.4 mg doses of tam- sulosin. He had a visual analog visual for pain (range 0- 10) of 7 secondary to the painful erection. At admission the physical examination showed: temper- ature 36,6°C, pulse 84/minute, respiratory rate 18/minute and blood pressure 137/88. Heart, lung, abdominal and neurologic examination were normal. Genital examination revealed no skin lesions, painless testicular examination with normal volume and a com- plete painful rigid erection with no tumescence of the glans. A urine analysis revealed microscopic hematuria with no other pathological signs, urine culture developed no bacterial growth 48 hours later, and hemogram was normal with no signs of hematologic disease. After eval- uation, a consultation for urologic evaluation was asked. After history taking and physical evaluation, the urolo- gist confirmed the diagnosis of ischemic priapism. To achieve detumescence, after administration of local anesthesia to the base of the penile shaft and while mon- itoring the heart rate and blood pressure of the patient, boluses of 200 microgram phenylephrine in a two milli- liter solution were injected directly in the corpora caver- nosa. After five boluses (1000 micrograms) and 20 min- utes, detumescence was achieved. No further procedures were needed. The patient was send home with the indi- cation to avoid tamsulosin intake and sexual intercourse for the next seven days. In the follow-up the patient had no new priapism episodes and reported no problems with erections and sexual intercourse. DISCUSSION Adverse events to different type of medications is one of the most important causes of priapism. The most com- mon drugs involved in priapism development are vaso- active intracavernosal injections, anti-psychotics, anti- depressants, cocaine, alcohol (Table 1). There are few published reports associating the consumption of alpha- blockers to the development of priapism, in particular tamsulosin. In a previous systematic review, 13 articles reported a cause-effect relation, among which only three cases were secondary to tamsulosin (5). In one of those cases, tamsulosin was associated to a partial thrombosis of the corpora cavernosa (6), and in a second case the asso- ciation of tamsulosin to a drug (Boceprevir-CYP3A4) that inhibits its degradation triggered a priapism episode (7). When analyzing our case, we were not able to find any other etiology of priapism in our patient. He was healthy, with no hematological or neurologic diseases, and the only two medications he had consumed in the last 48 hours were ketorolac and tamsulosin. There are no reports in the literature associating ketorolac with the development of priapism. As an alpha-blocker tamsu- losin would interfere with the detumescence mechanism that is mediated by adrenaline and nor-adrenaline acting on alpha-adrenergic receptors in the corpora cavernosa. Considering the previous case-reports and ours, it seems that the development of priapism would be independent of the number tamsulosin doses. Even though, tamsulosin related priapism has been rarely reported; the association is relevant considering that this medication is commonly prescribed by urologists to treat benign prostatic hyperplasia, which is an extremely fre- quent condition in general population. When prescribing tamsulosin, priapism is almost never mentioned as a potential side-effect, questionable our report together with previous ones suggest that patients should be counselled. CONCLUSIONS Tamsulosin is one of most prescribed medications in uro- logical practice, even though priapism has been rarely associated to its consumption, the risk exists, suggesting that patients should be counselled about it. AUTHORS CONTRIBUTION MM and FP contributed to the writing of the first draft of the report and the initial discussion. MM was involved in the care and therapy of the patient. ISF and PN reviewed the manuscript. MM is the guarantor of this work and, as such, had full access to all the data in the study and takes responsibility for the integrity of the data and the accu- racy of the data analysis. All authors read and approved the final manuscript. REFERENCES 1. Salonia A, Eardley I, Giuliano F, et al. European Association of Urology guidelines on priapism. Eur Urol. 2014; 65:480-489 2. Muneer, A. Comparison of EAU and UK guidelines on priapism. Journal of Clinical Urology. 2017; 11:127-131. Table 1. Drugs associated to the development of priapism. 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International Journal of Impotence Research. 2011; 23:95-98. 6. Kilinc M, Piskin S, Guven R, et al. Partial priapism secondary to tamsulosin: a case report and review of the literature. Andrologia. 2009; 21:199-201. 7. Hammond KP, Nielsen C, Linnebur SA, et al. Priapism induced by boceprevir-CYP3A4 inhibition and α-adrenergic blockade: case report. Clin Infect Dis. 2014; 58:e35-8. 195Archivio Italiano di Urologia e Andrologia 2019; 91, 3 Priapism and tamsulosin Correspondence Marcelo Marconi, MD (Corresponding Author) mmarconi@andro.cl Andrology Unit, Department of Urology, Pontificia Universidad Catolica de Chile, Cruz del Sur 177, Santiago (Chile) Pablo Pavez, MD info@andro.cl Ignacio San Francisco, MD isanfrancisco@med.puc.cl Department of Urology, Pontificia Universidad Católica de Chile, Santiago (Chile) Paulette Narvaez, MD kikinarvaez@gmail.com Department of Urology, Hospital Dipreca, Santiago (Chile) Marconi_Stesura Seveso 30/09/19 18:26 Pagina 195